In recent years, chairs have increasingly become ergonomically designed for comfort and healthful body support. Such chairs can be adjusted by the user to meet their specific anatomy. These adjustments include, for example, seat tilt, seat height, seat depth, seat glide, back height, and back tilt.
Armrests are usually designed to be secured in a fixed position on the chair. In an office environment, different people often use the same chair. Similarly, a person may perform several different tasks in the same chair. For example, a person may switch from writing on a desktop to working on a computer and prefer different arm positions for each task. Therefore, designers began constructing chairs with armrests that are adjustable to match the specific anatomy of a person while providing flexibility for quickly changing the armrests for another person or for the same person performing a different task.
Armrests in some chairs adjust vertically relative to the seat in order to accommodate variations in torso height and upper arm length. Also, armrests in some chairs adjust horizontally toward and away from the sides of the chair in order to accommodate variations in shoulder, torso, and buttock width. However, current armrests are unable to adjust horizontally forward and rearward relative to the front of the chair in order to accommodate variations in comfortable arm positioning.
The ability to adjust the armrests horizontally forward and rearward relative to the front of the chair has inherent problems since there are many other adjustments in an ergonomic chair. These other adjustments are controlled by an assortment of paddles and knobs located near the bottom of the seat. Due to the location of these paddles and knobs to the bottom of the seat, difficulties arise in positioning an apparatus near the bottom of the seat to permit unimpeded forward and rearward adjustment of the armrests. The configuration and mounting of the apparatus must allow enough room for the paddles and knobs to operate.
It would be desirable to provide an apparatus to adjust the horizontal armrest position forward and rearward relative to the front of the chair while providing clearance for other ergonomic adjustments on a chair. It would also be desirable to provide synchronized adjustment to both armrests in the forward and rearward direction relative to the front of the chair with only one control.